I got a PM an hour ago telling sugarcane, a grass, was “not sustainable” and blocked “essential services.” Here is my reply:
Like the Pennsylvania Dutch, have not been farming the same land, even without use of any chemical fertilizers, for 200+ years and now have "top soil" more that a foot thick! ?? Certainly farming is sustainable, but can´t grow that same crop on the same land years after year. They do use horse shit, well aged in piles for a year or so, and grow some clover, etc. in the field some years, which they then deep ploy under. - The horse pulling the plow can only plow about a foot deep. If not for that limitation, the top soil would be more than a foot deep now.
I never suggested that the 1% of arable land producing all the ethanol all the world´s liquid fueled cars will need about a decade or more hence, had to be grown on the same 1% every year. Perhaps in light of the facts, you will want to reconsider your "its not sustainable" statement? Done correctly, contour plowing, crop rotation, and occasional clover like cover some years plowed under (if you don´t want to add any ammonia) can IMPROVE soil quality as is done in and around Lancaster County, PA.
What "essential ecosystem services" do you speak of? - Just tell me (not the good peaceful Mennonites in living in the Lancaster PA region for more than 20 decades).
Sustainable, renewable, farming practices that have actually improved mature soils have been practiced for several hundred years by the Pennsylvania Dutch farmer.
* Google search on “Pennsylvania Dutch soil conservation practices” takes you directly to page 165.
In right column of same page you can read how terrible agriculture practices still are in much of the world – For example large goat heads eat the bark off trees and the roots of grasses, to make and expand deserts. The Sahara Deserts is still expanding southward rapidly, except for several experimental square mile plots, green dots as seen by astronauts, that were fenced to keep the goats out, which are now surounded by desert.
While climate changes did help convert the “Sahara Forest” into the “Sahara Desert”, many large tribes of Bedouins with even larger herds of “black goats” (now an almost extinct species) did more than half of the transformation by eating the young the forest seedling for hundreds of years. This could all be reclaimned in less than 100 years for food and fiber production! (as Israel has transformed desert into crop land in half that time.)
http://news.softpedia.com/news/Has-Sahara-Always-Been-a-Desert-47128.shtml said:
Sahara flourished the Neolithic culture which left the famous rock paintings found in Tassili n'Ajjer Mountains (above) and other areas of Sahara, depicting crocodiles, ostriches, rhinos, giraffes, buffaloes, hippopotamus and elephants, encountered today only in Africa at South of Sahara, but also oryx antelopes and gazelles. The Sahara was filled with lakes in the region of modern Niger and people hunted antelopes, while its mountains were covered by forests. Archaeologists encountered from hippopotamus and elephant bones to fishing harpoons.
After that, 4,500 years ago, the region turned into the arid desert we know today. In some Saharan mountains or patches, there are some savanna elements still persisting, like crocodiles, hyraxes and different shrub species. But human activity like deforestation, intensive grazing and farming sped up the phenomenon. And Sahara is still expanding southward: since 1900, the desert has gained a fringe over 250 km (155 mi) wide.
But 20 years ago, researchers using radar technology discovered in the depths of the rocks of the wide valleys, a web of "channels", some small, others wider, as broad as the Nile, which represent the dry riverbeds of the rivers that crossed Sahara thousands of years ago. Niger River once originated in Sahara. ... Even today, in the underground of Sahara, at 800 m (2500 feet) depth, there is a subterranean sea of fossil freshwater, compassing 620,000 cubic kilometers (150,000 cubic miles) over a surface of 6.5 million square kilometers (2.3 million square miles){Billy T notes: with 150,000 cubic miles of fresh water the Sahara could be reforested or partialy made into crop land.}
I.e. All large forests have a web of rivers that drain the forest rains. The Sahara Forest was no exception. The Amazon River is one too.
The average prevaling near-surface winds in the Northern Hemisphere blow towards the South* Thus, the Sahara Forest, if it still existed, would get from the Mediterranean Sea, more rain fall than the "land locked" Amazon Forest gets!. Forests tend to be efficient in retaining what rain fall they get.
* They are the cooler, more northern air masses moving back towards the equator, while the higher winds transport equatorial heat toward the poles. The Coriollis force bends them towards the East (Some Americans know on average the wind comes FROM the NW.) Continued demand for beautiful woods, like mahogany, by wealthy people may convert the Amazon Forest into a desert, without any assistance from goats, and if that happens, it will be much harder to re-forest than the Sahara. I have posted several times the economic mechanism which, despite Brazil´s strenuous efforts, is shrinking the Amazon forest every year. Here is a footnote from post 315 of this thread:
"... The rich desiring pretty woods, like mahogany, are destroying the Rain Forests. A wood from a single mahogany tree can be worth more than $8,000 {much more than a years salary at Brazil´s minium wage} in the US port of entry. Very illegal to cut them down in Brazil, but area is large and it only takes a day before it is converted into boards with labor cost of less than $10/ per day.
The valuable trees are selectively harvested by unemployed poor men, and then the forest is burned to hide the crime. After the locals can no longer get the cash they need by illegally catching and selling animals, especially parrots, they are reduced to subsistence farming the poor soil (a cow or two, some pigs and lots of chickens scratching for food among the fallen burnt trunks), but soon they give up and then some rich absentee land owner completes the clearing and seeds the land as pasture. (Grass will grow in almost any soil, with rain.) Some pasture is being displaced for food crops far to the south. There is no sugar cane grown in the old rain forest - it is more than 1000 miles away for the market for alcohol and cannot compete with the cane fields that are used. - Most of those are within 100 miles of either Rio or Sao Paulo. ..."
